The previous code unilaterally enabled filter functionality. Some
Mastodon-like servers -- like GoToSocial -- do not support filters, and
this resulted in user visible error messages when connecting to those
servers.
To fix this:
- Extend the set of supported server capabilities to include client and
server side filtering.
- Disable the filter preferences if the server does not support filters
and show a message explaining why it's disabled.
Extend the capabilities model to support this:
- Fetch server software name and version from the nodeinfo endpoints
(implementing the nodeinfo API and schema)
- Extend the use of kotlin-result to provide hierarchies of Error
classes and demonstrate how to chain errors and display more informative
messages without using exceptions.
Fixes#343
42219875e9